Underdrive pulleys

[freakypierced1]

http://www.stuffforyourranger.com/store/index.php?main_page=index&cPath=4_30_37


Does anyone have any experience with these? Are they worth the price and does it make a noticeable difference?

 

[Big Jim M]

Underdrive pullys are intended for high rpm engines such as drag racing, etc. There would be no gain from the way most of us drive. There may be some fuel saving if the vehicle being driven normally has an extreme low gear ratio and the engine is reving higher than most others at the same speed. However that saving prolly will NEVER result in saving the original cost of the pullys.
Using underdrive pullys on most of our engines could result in having not enough revs to charge the battery or enough fan speed to cool the engine.
Big JIm

 

[AllanD]

I laugh when I hear claims of underdrive pullies "saving power"
from various engine accessories...

From the alternator? No, the alternator has a voltage regulator that will
adjust the field current until it's maintaining the proper voltage, at lower
rpm it take more field current to produce the same output so underdrive
pullies will typically increase drag from the alternator.

From the P/S pump? Nope, any savings is trivial because the pump
is running on a bypass valve most of the time.

From the A/C? on most modern vehicles the A/C clutch cycles
so the only thing an underdrive pulley will do is increase the
percentage of the time the compressor has to run to maintain
system pressure.

As to the water pump? that might save some power, but at the risk of not
moving the coolant fast enough....

AD

 

[THE H.P FREAK]

HI!... I laugh when reading these posts. They do work. I've seen it a hundred times on the dyno. Ran them on my F-150 never had ANY problems with them. Gained 12RWH.P with them. I also run them on my new Ranger as well. Never had a problem with them. I luv when people say U/D pulleys don't work, electric fans do nothing, CAI's do nothing. Well funny that my RANGER went 16.01E.T. Then I added a electric fan, under drive crank pulley and a custom CAI and went 14.67E.T. ............ But they don't work. lol! F-150 on the dyno picked up 19RWH.P just switching to a electric fan.......

The only time I say stay away from U/D pulleys is if you have a big stereo system, or you run a large winch.

I get over 28MPG with my Ranger 4.0L with the above mentioned mods + I have 4.10 gears and a tune.

 

[freakypierced1]

Thanks for all the input guys

 

[BlackBII]

12 RWh.p.? Please.

Hell, you can gain that in weight savings by removing the money from your wallet and giving it to me, rather than spending it on UD pulleys.

 

[THE H.P FREAK]

12 RWh.p.? Please.

Hell, you can gain that in weight savings by removing the money from your wallet and giving it to me, rather than spending it on UD pulleys.

HI!... When your dealing with a 450H.P N/A engine, 12RWH.P is not much for a set of U/D pulleys.

 

[Chris.S.]

^^
I get a kick out of people trying to disagree with you as you obviously know your stuff...

 

[AllanD]

HI!... I laugh when reading these posts. They do work. I've seen it a hundred times on the dyno. Ran them on my F-150 never had ANY problems with them. Gained 12RWH.P with them. I also run them on my new Ranger as well. Never had a problem with them. I luv when people say U/D pulleys don't work, electric fans do nothing, CAI's do nothing. Well funny that my RANGER went 16.01E.T. Then I added a electric fan, under drive crank pulley and a custom CAI and went 14.67E.T. ............ But they don't work. lol! F-150 on the dyno picked up 19RWH.P just switching to a electric fan.......

The only time I say stay away from U/D pulleys is if you have a big stereo system, or you run a large winch.

I get over 28MPG with my Ranger 4.0L with the above mentioned mods + I have 4.10 gears and a tune.

Under the limited useage of the drag strip you'll see a small ifference like you obviously did.

But on a street driven truck?

I call Bullshit.

AD

 

[Big Jim M]

But Allan

He gets OVER 28mpg with them modifications! In a Ranger with a 4:11 in it..
Big Jim

 

[AllanD]

People still don't believe that I could get a repeatable 25mpg with a 2.9 in
a truck with 4.10's and 235's

I now have the same truck with the same tires and a 4.10 and an
absolute best of 22mpg

But the one that really sets me off is the people talking about the "Cold air intakes"
when every ranger made altready had one that they needed to remove to put their aftermarket "stuff" in it's place.

They'll point to the heat riser and say that heats the intake...
really tweeks me because that thing is closed off most of the time...

AD

 

[Bob Ayers]

Under the limited useage of the drag strip you'll see a small ifference like you obviously did.

But on a street driven truck?

I call Bullshit.

AD

+1

 

[mjonesjr]

I have used them.

They work as long as they are not the only modification to your 4.0.

If you have a 3.0, they are a big improvement.

 

[Bob Ayers]

I have used them.

They work as long as they are not the only modification to your 4.0.

If you have a 3.0, they are a big improvement.

Re-read AllanD's post......his points apply to the 3.0L also!

 

[Blueox]

I installed one...

My goal was better mpg and I got it. I now average 18.4 overall with maybe 60% city. Best on a trip was 22.0. These figures are based on a long term tracking of my mileage, not a tank or two.

So when gas gets back to $4 or more and it will, there is some savings. How long will it take to pay for the pulley? Don't care. Just trying to lower my carbon footprint.